Kickoff is at 3:30. Carnage to follow, a few seconds later. And sustain. With pain.

When the 49ers and Seahawks meet Sunday afternoon, it will not merely be the most physical game of the entire postseason. It will be a throwback to an ancient time.

Remember those days of, say, 2010 or 2011? You know, before the NFL began passing anti-violence rules in earnest? Well, this NFC title game will be more like that. You can decide if that’s better or worse for humanity. But this is not a moral debate. This is the way both teams want to play.

The 49ers and Seahawks are Big Bang teams. Sometimes you wonder if they would rather just line up and run into each other for pleasure, with no football even on the field. They each want to dominate physically.

“Seattle is definitely that,” 49ers defensive lineman Justin Smith said this week in agreement. “We’re definitely that. Just what it’s going to come down to: Two teams that want to run the ball, play good defense. … I think we’re pretty much identical from that aspect of getting after each other.”

What’s compelling, though, is how the two teams have kept that brutality bar raised, even as the NFL tries to make the game less cruel, to make it be more about finesse — more about the offensive numbers that build fantasy league interest. New regulations have been issued to outlaw “targeting” collisions, or other blows to the head, or simply hits on “defenseless” players.

“They’ve been trying to change the game a lot from that standpoint,” Smith agreed. “But as long as you have a helmet on and you can still tackle the ball carrier, it’s going to be football. I think that’s what is always going to make the best teams. It’s always going to come down to blocking and tackling until they take that away.”

The 49ers and Seahawks have sort of adjusted to the new rules. Sort of. Because frankly, the rules do seem to be more, um, fluid when the two teams play each other.

Example: The Seahawks’ defensive backs have an unwritten strategy of basically committing pass interference on every play, because they realize that the referees won’t call pass interference on every play. Similar standards exist at the scrimmage line. The 49ers, when they’ve had success against the Seahawks, have responded in the same way.

And fantasy points aside, it has been stunning and compelling football to watch. Consider: Seattle has allowed just one 49er touchdown in three of the past four games between the teams (and just a field goal in the 29-3 Seahawks win Sept. 15) — and yet the 49ers still won two of those games.

Can they win again Sunday?

The 49ers are certainly capable of beating Seattle. Over the past two months, the 49ers have been capable of beating anyone. But their past two trips to the decibel funhouse of CenturyLink Field — both with Colin Kaepernick at quarterback — have resulted in two convincing defeats. There is no way to forecast a 49ers’ victory in this stadium until they prove they can once more win a game in this stadium.

The call here is Seahawks by 20-17. The call is also for an afternoon of injury timeouts, by both sides. In terms of physical matchups, the only recent equivalent would be the recent series of games between the Pittsburgh Steelers and Baltimore Ravens, two teams with a similar loathing for each other and a similar base level of violence.

Actually, in that aspect, the Seahawks-49ers mojo brings more to mind the nearly sadistic confrontations between the Steelers and the Raiders in the 1970s. In those games, Pittsburgh defensive tackle “Mean” Joe Greene and Oakland center Jim Otto would jointly ask the referees to stop calling personal foul penalties so that the two future Hall of Famers could manhandle each other in the trenches with no constraints.

It has not been quite that lawless in the 49ers-Seahawks series. But it has been at least that manly since 2011, when Jim Harbaugh took over as the 49ers’ head coach. His predecessor, Mike Singletary, liked to talk about playing “physical with an ‘F.’ ” But it wasn’t until Harbaugh brought his “smart hostility” philosophy from Stanford that the 49ers truly became a Big Bang team.

Initially, that caught opponents by surprise, as the 49ers blitzed out to a 13-3 record in Harbaugh’s first season. But the Seahawks were the first to catch on — coach Pete Carroll was familiar with the method from his time at USC facing Harbaugh — and figure out that the best way to counter Big Bang football was with Bigger Bang football. The Seahawks made it a mission to hit the 49ers in the mouth harder than the 49ers hit them.

And the strategy has been successful — at least on Seattle’s home turf. Vernon Davis, the 49ers tight end, has not finished the past two games here. He exited in 2012 with a concussion. Back in September, it was a hamstring injury. Other 49ers players — including Eric Reid, Mario Manningham and Ian Williams — have also been hurt and gone to the sideline in those two games, during which the Seahawks have outscored the 49ers by 71-16.

Seattle has not escaped its own pain and suffering against the 49ers, of course. And there will be more of it Sunday. One of Harbaugh’s mantras the past two months has been that this journey is only “for the tough.” The winner Sunday will be the toughest team at the Super Bowl.

Researchers said Sunday the mass die-off occurred because unusually large amounts of sea ice forced penguin parents to travel farther in search of food for their young. By the time they returned, only two out of thousands of chicks had survived.